Football 101: Offensive and Defensive Line Assignments

Football fans are smart individuals, but there is more to the game than the average fans sees on every down. In the "Football 101" series, you'll get a look at the assignments, plays and schemes that make the game of football so diverse, complicated and intricate.

Up first, the line of scrimmage.

Defining the basic offensive line alignment—including gaps—is something that most offensive coaches will start drilling to their players on the first day of camp. This is true from PeeWee football all the way up to the NFL. Same for the defensive side of the ball, where players must learn the different positions and the technique the coaches want them to line up in.

Above is a diagram showing the different alignments in a basic NFL defense. There are some variations in terms of the number of players down along the defensive line, but this represents the offensive gaps (in blue) versus the different defensive line techniques (in red).

This is a basic look at each position, but what are their job titles on the defensive side of the ball? The most common techniques used are:

9-Technique: An outside pass-rusher who takes on a wide stance to generate distance between himself and the end blocker on the line of scrimmage. Example: Trent Cole, Philadelphia Eagles

6-Technique: A 4-3 defensive end who takes on the outside shoulder of the tackle, or is head-up on the tight end. Example: Julius Peppers, Chicago Bears

5-Technique: Generally a 3-4 defensive end, whose job is to stop the run in Gaps C and B. For this reason, 3-4 defensive ends are referred to often as "two-gap" players. Example: Justin Smith, San Francisco 49ers

3-Technique: A 4-3 defensive tackle whose job is to rush the quarterback through the B gap, splitting the guard and tackle on his side of the line. Example: Ndamukong Suh, Detroit Lions

0-Technique: A nose tackle who is asked to stuff both A gaps and limit blockers and runners from coming through the middle. Example: Vince Wilfork, New England Patriots

The New England Patriots' 3-4 Shift defense

As the NFL progresses and changes, there are new adaptations of the basic 4-3 or 3-4 defense. The Philadelphia Eagles use a Wide-9 defense, which puts their speedy defensive ends out past the end-man on the offensive line for better pass-rushing leverage. As the game changes to more of a passing league, this defense could catch fire much like the 3-4 defense did under Dick LeBeau in Pittsburgh.